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// SPDX-License-Identifier: GPL-2.0
// Copyright (c) 2020 Facebook
#include <linux/ptrace.h>
#include <linux/bpf.h>
#include <bpf/bpf_helpers.h>
#include <bpf/bpf_tracing.h>
#define VAR_NUM 2
struct hmap_elem {
struct bpf_spin_lock lock;
int var[VAR_NUM];
};
struct {
__uint(type, BPF_MAP_TYPE_HASH);
__uint(max_entries, 1);
__type(key, __u32);
__type(value, struct hmap_elem);
} hash_map SEC(".maps");
SEC("freplace/handle_kprobe")
int new_handle_kprobe(struct pt_regs *ctx)
{
struct hmap_elem zero = {}, *val;
int key = 0;
val = bpf_map_lookup_elem(&hash_map, &key);
if (!val)
return 1;
/* spin_lock in hash map */
bpf_spin_lock(&val->lock);
val->var[0] = 99;
bpf_spin_unlock(&val->lock);
return 0;
}
char _license[] SEC("license") = "GPL";
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